Subtract 20/40 from 21/50
21/50 - 20/40 is -2/25.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 40 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 50 × 4 = 200,
21/50 = 21 × 4/50 × 4 = 84/200 - Likewise, for the 2nd fraction, since 40 × 5 = 200,
20/40 = 20 × 5/40 × 5 = 100/200 - Subtract the two like fractions:
84/200 - 100/200 = 84 - 100/200 = -16/200 - After reducing the fraction, the answer is -2/25
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